We compare Icelandic and European records of volcanic ash fallout over last 1000 years. We estimate the average return interval for ash fallout over northern Europe to be 44±7 years44±7 years. Ash fallout over Europe is more common than previously proposed (average of 56±9 years56±9 years). We estimate a 20% chance of an ash cloud over northern Europe in any 10 year period. Icelandic eruptions with a VEI ≥ 4 pose the greatest threat of ash fallout over northern Europe.